DESCRIPTION (provided by investigator): Mexican-American elderly suffer from higher prevalence of diabetes and more complications than most ethnic groups. Diabetes has been associated in other research with a higher risk of both vascular and Alzheimer's dementia. This research will compare the association between stressors, physiologic stress response and neurocognitive functioning, dementia, and structural brain changes from MRI, in a subsample of 400 diabetics and 400 nondiabetics in an ongoing population-based cohort study of 1,789 Mexican-American elderly aged 60+. The Sacramento Area Latino Study on Aging (SALSA) study participants are being followed for 30 chronic diseases, functional status, cognitive impairment and dementia. Prevalence of diabetes in this study is 30 percent; SALSA diabetics have a 2-fold higher risk of dementia and severe cognitive impairment than nondiabetics in this sample and 45 percent of demented cases are diabetics. SALSA diabetics also suffer from greater functional impairment, higher stroke risk and depressive symptoms. The subsample will be stratified on diabetic status and oversampled for demented or severely cognitively impaired (CIND) cases. The differential role of hemostatic factors, lipids, inflammatory factors (homocysteine, creactive protein), and cortisol on cognitive function in diabetics and nondiabetics will be examined. We expect that: (a) diabetics are exposed to higher levels of stress, and (b) respond differently to stress as indicated by abnormal cortisol levels, increased fibrinogen, CRP or homocysteine, (c) have higher HBA1c levels when exposed to/responding to stress, and that (d) diabetes, inflammatory and hemostatic factors, abnormal cortisol and higher HBA1c levels may be associated with structural brain changes such as white matter, smaller hippocampal volume, and more and larger lacunae. Further, the association between depression and cognitive impairment and brain changes in this study will be considered. This study offers an opportunity to understand the role of environmental and physiologic stress in neurological consequences of diabetes and further examine the link between diabetes and dementia.